For me, it didn't quite live up to the great reviews.
The massive hype for this film convinced me to watch it but I found some aspects very disappointing: 1) the distracting, guttural, screeching and clanging music did not support the action, and often competed with the dialogue in the quieter scenes. I think Hans Zimmer would have been a better composer choice for a film of this magnitude and scope. 2) the alternating black & white to color scenes depending on time frames was extremely distracting. 3) The editing was choppy and some scene sequences didn't flow. 4) The sex scenes with Cillian and Florence Pugh were gratuitous and poorly done, plus they had no screen chemistry.
The positives: 1) fantastic, intensely riveting performances by the talented Cillian Murphy and Robert Downey Jr. The movie is worth seeing just for them and I would expect Oscar nods for both. Casey Affleck & Gary Oldman were superb and I wished their roles were larger. Emily Blunt is wonderful no matter the movie and she dependably delivers here. 2) The special effects are mind-blowing and jaw-dropping. Words don't do them justice.
All in all, I give the movie a thumbs up but I've seen better.